SmogRank / Episodes / India

India, Bangladesh and Nepal, October 2026

For 4 days, from 3 to 6 October 2026, 18 cities in India, Nepal and Bangladesh had PM2.5 at least twice their usual for the time of year. The worst reading was Dhaka, Dhaka Division, Bangladesh: 118.3 µg/m³ on 6 October, about 2.2× its usual 54.6. Ended 6 October.

Likely smoke from firesFires were detected within 300 km of the city on 68% of the counted city-days. Satellites see crop, field and forest fires alike, so this doesn't say which burned.
Cities reached18in 3 countries
Days43 to 6 October 2026
Worst day3 October12 cities counted
Furthest above usual6.5×Sasarām

Day by day

3 October 12 cities at twice their usual or more
KatiharBhāgalpurRānīganjĀsansolKishanganjJhariaSaharsaSiliguriBihār SharīfRājgīrHājīpurGayaPatnaPhuntsholingRairangpurChāpraArrahBarbilJodaJājangSiwānKoīraRourkelaBettiahNalbāriKahi KuchiGuwahatiDispurBelpaharGorakhpurSiddharthanagarButwālKathmanduArāriaSamāstipurBaripādaKolkataDhakaKeonjhargarhPurniaDurgapurHaldiaMothīhāriMuzaffarpurMungerGangtokShrīrāmpurAgartalaBegusaraiSasarām

On the map: 103 fire detections.

30 Sep1 Oct23456789
Every measured city in the area, coloured by its PM2.5 that day; a dark ring marks a city at twice its usual or more. Bars: cities counted each day, coloured by their median level. Choose a day or press play; without JavaScript, the days link to that day's world ranking.
  • Fires, seenHeat NASA satellites detected that day; bigger and glowing means more detections in the area. Farm burning and other fires count too, not only wildfires.
  • Volcanic ash, warnedA volcano with an ash warning for aircraft that day; shaded where forecasters saw the ash cloud.

Under the cities, for each UTC day: fires NASA satellites detected, smoke NOAA analysts traced and volcanic ash warnings for aircraft. They show what was in the air, not that it caused the readings. Mapped for 9 of the 10 days shown.

Fires: NASA FIRMS (VIIRS). Traced smoke: NOAA Hazard Mapping System. Volcanic ash: aviation ash warnings (SIGMETs) via NOAA's Aviation Weather Center.

How it spread

SasarāmSasarām, 30 September: 41.1 µg/m³Sasarām, 1 October: 58.2 µg/m³Sasarām, 2 October: no readingSasarām, 3 October: 83.8 µg/m³, 6.5× its usual 12.9Sasarām, 4 October: 61.4 µg/m³, 4.1× its usual 15.1Sasarām, 5 October: 47.6 µg/m³, 3.0× its usual 16.0Sasarām, 6 October: 52.7 µg/m³, 3.2× its usual 16.7Sasarām, 7 October: 42.9 µg/m³Sasarām, 8 October: no readingSasarām, 9 October: no readingKolkataKolkata, 30 September: 65.1 µg/m³Kolkata, 1 October: 58.5 µg/m³Kolkata, 2 October: no readingKolkata, 3 October: 71.0 µg/m³, 2.5× its usual 28.4Kolkata, 4 October: 70.3 µg/m³, 2.4× its usual 28.8Kolkata, 5 October: 68.5 µg/m³, 2.3× its usual 30.3Kolkata, 6 October: 74.9 µg/m³, 2.2× its usual 33.7Kolkata, 7 October: 52.9 µg/m³Kolkata, 8 October: no readingKolkata, 9 October: no readingArāriaArāria, 30 September: 58.6 µg/m³Arāria, 1 October: 68.1 µg/m³Arāria, 2 October: no readingArāria, 3 October: 68.6 µg/m³, 2.1× its usual 33.2Arāria, 4 October: no readingArāria, 5 October: 43.4 µg/m³Arāria, 6 October: 54.0 µg/m³Arāria, 7 October: 44.2 µg/m³Arāria, 8 October: no readingArāria, 9 October: no readingBaripādaBaripāda, 30 September: 47.0 µg/m³Baripāda, 1 October: 50.1 µg/m³Baripāda, 2 October: no readingBaripāda, 3 October: 66.4 µg/m³, 2.3× its usual 29.3Baripāda, 4 October: 66.7 µg/m³, 2.2× its usual 30.6Baripāda, 5 October: 62.3 µg/m³Baripāda, 6 October: 57.2 µg/m³Baripāda, 7 October: 49.7 µg/m³Baripāda, 8 October: no readingBaripāda, 9 October: no readingMungerMunger, 30 September: 54.6 µg/m³Munger, 1 October: 49.8 µg/m³Munger, 2 October: no readingMunger, 3 October: 64.2 µg/m³, 2.1× its usual 31.2Munger, 4 October: no readingMunger, 5 October: 90.8 µg/m³, 2.7× its usual 33.5Munger, 6 October: 81.5 µg/m³, 2.3× its usual 35.4Munger, 7 October: no readingMunger, 8 October: no readingMunger, 9 October: no readingDurgapurDurgapur, 30 September: 39.0 µg/m³Durgapur, 1 October: 43.9 µg/m³Durgapur, 2 October: no readingDurgapur, 3 October: 63.4 µg/m³, 2.3× its usual 27.7Durgapur, 4 October: 64.1 µg/m³, 2.3× its usual 27.7Durgapur, 5 October: 46.5 µg/m³Durgapur, 6 October: 31.6 µg/m³Durgapur, 7 October: 28.9 µg/m³Durgapur, 8 October: no readingDurgapur, 9 October: no readingShrīrāmpurShrīrāmpur, 30 September: 51.3 µg/m³Shrīrāmpur, 1 October: 56.3 µg/m³Shrīrāmpur, 2 October: no readingShrīrāmpur, 3 October: 62.7 µg/m³, 2.8× its usual 22.3Shrīrāmpur, 4 October: 64.2 µg/m³, 2.8× its usual 22.9Shrīrāmpur, 5 October: 56.9 µg/m³, 2.3× its usual 24.8Shrīrāmpur, 6 October: 57.4 µg/m³, 2.1× its usual 27.0Shrīrāmpur, 7 October: 50.3 µg/m³Shrīrāmpur, 8 October: no readingShrīrāmpur, 9 October: no readingPurniaPurnia, 30 September: 63.0 µg/m³Purnia, 1 October: no readingPurnia, 2 October: no readingPurnia, 3 October: 58.0 µg/m³, 2.3× its usual 25.6Purnia, 4 October: no readingPurnia, 5 October: 58.3 µg/m³Purnia, 6 October: 54.8 µg/m³Purnia, 7 October: 52.4 µg/m³Purnia, 8 October: no readingPurnia, 9 October: no readingAgartalaAgartala, 30 September: 52.1 µg/m³Agartala, 1 October: 46.1 µg/m³Agartala, 2 October: no readingAgartala, 3 October: 57.6 µg/m³, 3.0× its usual 19.1Agartala, 4 October: no readingAgartala, 5 October: 66.8 µg/m³, 3.4× its usual 19.4Agartala, 6 October: 75.3 µg/m³, 3.9× its usual 19.4Agartala, 7 October: 60.4 µg/m³Agartala, 8 October: no readingAgartala, 9 October: no readingBegusaraiBegusarai, 30 September: 37.6 µg/m³Begusarai, 1 October: 41.5 µg/m³Begusarai, 2 October: no readingBegusarai, 3 October: 55.8 µg/m³, 4.8× its usual 11.7Begusarai, 4 October: 50.1 µg/m³, 4.3× its usual 11.7Begusarai, 5 October: 60.4 µg/m³, 5.2× its usual 11.7Begusarai, 6 October: 35.6 µg/m³, 3.0× its usual 11.8Begusarai, 7 October: no readingBegusarai, 8 October: no readingBegusarai, 9 October: no readingHaldiaHaldia, 30 September: 43.8 µg/m³Haldia, 1 October: 42.6 µg/m³Haldia, 2 October: no readingHaldia, 3 October: 53.2 µg/m³, 2.5× its usual 21.1Haldia, 4 October: no readingHaldia, 5 October: 54.1 µg/m³, 2.4× its usual 22.2Haldia, 6 October: 50.4 µg/m³, 2.2× its usual 23.4Haldia, 7 October: 43.1 µg/m³Haldia, 8 October: no readingHaldia, 9 October: no readingGangtokGangtok, 30 September: 17.1 µg/m³Gangtok, 1 October: 23.1 µg/m³Gangtok, 2 October: no readingGangtok, 3 October: 25.6 µg/m³, 2.8× its usual 9.0Gangtok, 4 October: 23.1 µg/m³Gangtok, 5 October: no readingGangtok, 6 October: 16.7 µg/m³Gangtok, 7 October: no readingGangtok, 8 October: no readingGangtok, 9 October: no readingMuzaffarpurMuzaffarpur, 30 September: 31.8 µg/m³Muzaffarpur, 1 October: 32.1 µg/m³Muzaffarpur, 2 October: no readingMuzaffarpur, 3 October: 27.8 µg/m³Muzaffarpur, 4 October: 65.9 µg/m³, 2.5× its usual 26.4Muzaffarpur, 5 October: 51.2 µg/m³Muzaffarpur, 6 October: 45.3 µg/m³Muzaffarpur, 7 October: 43.5 µg/m³Muzaffarpur, 8 October: no readingMuzaffarpur, 9 October: no readingMothīhāriMothīhāri, 30 September: 23.8 µg/m³Mothīhāri, 1 October: 42.6 µg/m³Mothīhāri, 2 October: no readingMothīhāri, 3 October: no readingMothīhāri, 4 October: 60.6 µg/m³, 2.5× its usual 24.3Mothīhāri, 5 October: 51.2 µg/m³, 2.1× its usual 24.3Mothīhāri, 6 October: 43.9 µg/m³Mothīhāri, 7 October: no readingMothīhāri, 8 October: no readingMothīhāri, 9 October: no readingSamāstipurSamāstipur, 30 September: no readingSamāstipur, 1 October: 42.0 µg/m³Samāstipur, 2 October: no readingSamāstipur, 3 October: 49.1 µg/m³Samāstipur, 4 October: no readingSamāstipur, 5 October: 89.9 µg/m³, 2.1× its usual 43.5Samāstipur, 6 October: 53.7 µg/m³Samāstipur, 7 October: no readingSamāstipur, 8 October: no readingSamāstipur, 9 October: no readingKathmanduKathmandu, 30 September: 29.0 µg/m³Kathmandu, 1 October: 34.4 µg/m³Kathmandu, 2 October: 36.8 µg/m³Kathmandu, 3 October: 40.9 µg/m³Kathmandu, 4 October: 40.8 µg/m³Kathmandu, 5 October: 45.9 µg/m³, 2.1× its usual 22.2Kathmandu, 6 October: 39.5 µg/m³Kathmandu, 7 October: 32.6 µg/m³Kathmandu, 8 October: no readingKathmandu, 9 October: no readingKeonjhargarhKeonjhargarh, 30 September: 31.2 µg/m³Keonjhargarh, 1 October: 34.5 µg/m³Keonjhargarh, 2 October: no readingKeonjhargarh, 3 October: 24.9 µg/m³Keonjhargarh, 4 October: 24.4 µg/m³Keonjhargarh, 5 October: 35.9 µg/m³, 2.3× its usual 15.4Keonjhargarh, 6 October: 33.8 µg/m³, 2.1× its usual 16.0Keonjhargarh, 7 October: 16.7 µg/m³Keonjhargarh, 8 October: no readingKeonjhargarh, 9 October: no readingDhakaDhaka, 30 September: 72.6 µg/m³Dhaka, 1 October: 81.1 µg/m³Dhaka, 2 October: 82.2 µg/m³Dhaka, 3 October: 81.2 µg/m³Dhaka, 4 October: 99.9 µg/m³Dhaka, 5 October: 102.6 µg/m³Dhaka, 6 October: 118.3 µg/m³, 2.2× its usual 54.6Dhaka, 7 October: 99.1 µg/m³Dhaka, 8 October: no readingDhaka, 9 October: no reading30 Sep1 Oct23456789
Every counted city, in the order the episode reached them, 3 days before to 3 after. Each square is a day, coloured by that day's PM2.5; outlined: at twice the city's usual or more.
Good0–50
Moderate51–100
Sensitive groups101–150
Unhealthy151–200
Very unhealthy201–300
Hazardous301+

Every city it reached

CityDaysHighestUsualAbove usual
SasarāmBihar, India4 83.83 October12.96.5×
BegusaraiBihar, India4 60.45 October11.75.2×
AgartalaTripura, India3 75.36 October19.43.9×
ShrīrāmpurWest Bengal, India4 64.24 October22.92.8×
GangtokSikkim, India1 25.63 October9.02.8×
MungerBihar, India3 90.85 October33.52.7×
MuzaffarpurBihar, India1 65.94 October26.42.5×
MothīhāriBihar, India2 60.64 October24.32.5×
HaldiaWest Bengal, India3 54.15 October22.22.4×
DurgapurWest Bengal, India2 64.14 October27.72.3×
PurniaBihar, India1 58.03 October25.62.3×
KeonjhargarhOdisha, India2 35.95 October15.42.3×
DhakaDhaka Division, Bangladesh1 118.36 October54.62.2×
KolkataWest Bengal, India4 74.96 October33.72.2×
BaripādaOdisha, India2 66.74 October30.62.2×
SamāstipurBihar, India1 89.95 October43.52.1×
ArāriaBihar, India1 68.63 October33.22.1×
KathmanduBagmati Province, Nepal1 45.95 October22.22.1×

Daily means in µg/m³, over the days each city counted in this episode. Highest: its highest of those days. Usual: the city's median for the time of year of that day (its days within 21 days of the date, every year, leaving out the week around it). Above usual: its highest day against that, with a usual under 5 µg/m³ taken as 5.

Against other episodes in India and Nepal

Number 15 of 64 episodes in India and Nepal since our records began, by cities reached.

Bars: cities reached; colour: the level of the episode's highest daily reading. All 64.

Use this page

SmogRank, India, Bangladesh and Nepal, October 2026: 18 cities with PM2.5 at twice their usual or more, 3 to 6 October 2026, smogrank.com/episodes/2026-10-india-bangladesh-and-nepal (accessed 9 October 2026).

Download top 10 (PNG)

You're welcome to reuse a single chart, image or figure with this citation and a link. Terms.

An episode is a run of days when many cities close to each other (four or more within 350 km on a day, 8 or more in all) each had a daily PM2.5 mean of at least 25 µg/m³ and at least 2 times their usual for that time of year. Found in our own measurements, not picked by hand. How we find episodes. Values are each city's daily mean of its own monitors; causes are the usual kinds for a pattern like this, not a confirmed source. Fire detections from NASA FIRMS; smoke maps from NOAA HMS. Dust: contains modified Copernicus Atmosphere Monitoring Service information 2026. Neither the European Commission nor ECMWF is responsible for any use that may be made of the Copernicus information or data it contains.